--I called you at half past nine this morning, but there was no answer.

--Oh, sorry, I ______ with my cousin in the supermarket.[ ]

A. shop    

B. was shopping  

C. shopped      

D. will shop

当启动加油机时，加油机系统中电机即被启动，泵在电机带动下工作，将地下储油罐中的燃油经过滤吸入泵腔，油液在泵内被加压，进入（）。

（A）测量变换器

（B）油气分离器

（C）电磁阀

（D）视油器